Carbon-coated silica

Salt-inclusion solids described herein were synthesized at high temperature (>500°C) in the presence of reactive alkali and alkaline-earth metal halide salt media. For single crystal growth, an extra amount of molten salt is used, typically 3 5 times by weight of oxides. The reaction mixtures were placed in a carbon-coated silica ampoule, which was then sealed under vacuum. The reaction temperature was typically set at 100-150 °C above the melting point of employed salt. As shown in the schematic drawing in Fig. 16.2, the corresponding metal oxides were first dissolved conceivably via decomposition because of cor-... 

There is a variety of miscellaneous fillers that are of interest for reinforcing elastomers such as PDMS. Examples are ground-up silica xerogels,119 carbon-coated silica,120 and functionalized silica particles.121-123... 

To ascertain which of the above-mentioned mechanisms is responsible for the appearance of signal 2, we studied the adsorption of benzene and methane on the dehydrated surfaces of carbon-coated silicas (Fig. 16). The spectra of the starting silica gel are also included. It was assumed that these adsorbates, as well... 

Dr. Turov and Professor Leboda combine their expertise in nuclear magnetic resonance and adsorption phenomena to propose a new tool for a more incisive analysis of adsorbate-adsorbent interactions. Such an analysis is of critical importance in so many applications where it is becoming increasingly clear that adsorbate-carbon interactions are governed by both pore size and surface chemistry effects. These range from the ubiquitous water adsorption to the design of carbon-coated silicas with tailored ratios of hydrophobic to hydrophilic surface sites. 

Kohls, D. Beaucage, G. Pratsinis, S. E. Kammler, H. Skillas, G., Carbon Coated Silica for Elastomer Reinforcement. In Filled and Nanocomposite Polymer Materials, Hjelm, R. J. Nakatani, A. L Gerspacher, M. Krishnamoorti, R., Eds. Materials Research Society Warrendale, PA, 2001 Vol. 661. 

This paper describes the catalytic activity of nickel phosphide supported on silica, alumina, and carbon-coated alumina in the hydrodesulfurization of 4,6-dimethyldibenzothiophene. The catalysts are made by the reduction of phosphate precursors. On the silica support the phosphate is reduced easily to form nickel phosphide with hi catalytic activity, but on the alumina support interactions between the phosphate and the alumina hinder the reduction. The addition of a carbon overlayer on alumina decreases the interactions and leads to the formation of an active phosphide phase. 

Other composite photocatalysts were prepared by mounting immobilized anatase particles on mesoporous silica and silica beads [189-191], The behavior of anatase-mounted activated carbons was also studied in detail [192-194], It was even suggested that carbon-coated anatase exhibits better performance in photocatalysis than anatase itself, demonstrating high adsorptivity, inhibition of interaction with organic binders, etc. [195,196],... 

Chang, Y. Z., Chen, Y. R., and Her, G. R. (2001). Sheathless capillary electrophoresis/electrospray mass spectrometry using a carbon-coated tapered fused-silica capillary with a beveled edge. Anal. Chem. 73, 5083-5087. 

Silica tiles with a borosilicate coating insulation-LRSI Pyrolized carbon-carbon coated with silicon carbide (SiQ... 

YZ Chang, GR Her. Sheathless capillary electrophoresis—electrospray mass spectrometry using a carbon-coated fused-silica capillary. Anal Chem 72 626— 630, 2000. 

Name 2-Ethylhexyl carbonate coated or bonded on cholesteryl silica (room temperature liquid crystal) Structure ... 

Diatoms are unicellular, photosynthetic microalgae that are abundant in the world s oceans and fresh waters. It is estimated that several tens of thousands of different species exist sizes typically range from ca 5 to 400 pm, and most contain an outer wall of amorphous hydrated silica. These outer walls (named frustules ) are intricately shaped and fenestrated in species-specific (genetically inherited) patterns5,6. The intricacy of these structures in many cases exceeds our present capability for nanoscale structural control. In this respect, the diatoms resemble another group of armored unicellular microalgae, the coccolithophorids, that produce intricately structured shells of calcium carbonate. The silica wall of each diatom is formed in sections by polycondensation of silicic acid or as-yet unidentified derivatives (see below) within a membrane-enclosed silica deposition vesicle 1,7,8. In this vesicle, the silica is coated with specific proteins that act like a coat of varnish to protect the silica from dissolution (see below). The silica is then extruded through the cell membrane and cell wall (lipid- and polysaccharide-based boundary layers, respectively) to the periphery of the cell. 

The presence of Si Is curve indicates that during the preparation of samples for recording XPS s, fractures of the composite silica skeleton appeared, which have no carbon coating, and that the carbon coating is not homogeneous. 

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